The invention relates generally to computer system graphics features, and more particularly to performance and power consumption of computer graphics adapters.
Computer systems utilize graphics for almost all aspects of user interaction. Conventional computer output is predominately graphical in nature, as exhibited by windowing environments, such as WINDOWS(copyright) 98 developed by MICROSOFT(copyright) Corporation. Windowing environments and other user interfaces also allow user input through graphics controls with devices such as a keyboard, a mouse, or a joystick. Additionally, graphical input and output are used for computer video game interaction. These video games, in turn, typically require high speed graphics processing. In order to meet demanding graphics processing standards, many graphics adapters now include dedicated controller chips.
Continuing advancements in semiconductor manufacturing processes enable the development of controller chips that operate at increasingly higher frequencies. Controller chips that operate at high clock speeds typically consume more power than controller chips running at lower clock speeds. Unfortunately, these high speed controller chips may cause the graphics subsystems to consume a substantial amount of power, a consumption that may deplete battery power sources used to power portable computers and other computing devices that have a limited power capacity.
In one embodiment, the invention provides a method to reduce power consumption in a computer system that has a graphics adapter. The method includes determining a power state of the system and regulating a frequency of operation of the graphics adapter in response to the power state. In another embodiment of the invention, a graphics adapter is provided that includes a clock device to regulate operation of the adapter and a routine to modify a frequency of the clock device in response to a power state. In yet another embodiment, the invention provides a computer system having a graphics adapter and a power source with a power state. Also included in the computer system are a clock device to regulate operation of the graphics adapter and a routine to modify a frequency of the clock device in response to a power state.